Printing telegraph receiver



June 26, 1951.. R. D. SALMON PRINTING TELEGRAPH RECEIVER s Shets-Shet 1 Filed Aug. 19, 1947 INVENTO'R ATTORNEY June 26, 1951 v R, D. SALM ON 2,558,003

PRINTING TELEGRAPH RECEIVER 5 Sheets-Sheet 2 Filed Aug. 19, 1947 INVENTOR REG/N440 0. 64LMO ATTORNEY June 26, 1951 R. D. SALMON PRINTING TELEGRAPH RECEIVER 5 Sheets-Sheet 3 Filed Aug. 19', 1947 I III llllilllv H m vi INVENTOR Rial/WILD 0 SALMON ATTORNEY June 26, 1951 R. D. SALMON PRINTING TELEGRAPH RECEIVER 5 Sheets-Sheet 4 Filed Aug. 19, 1947 BY I ATTORNEY 5 Sheets-Sheet 5 R. D. SALMON PRINTING TELEGRAPH RECEIVER June 26,1951

Filed Aug. 19, 1947 INVENTOR IPEGV/V/IZD 0. 541 10 ATTORNEY syn/ado 9,7

0 WW Mu m W x W P u w a m a a s 4 01 m w m A W ww a w a 1 a 8 UV. m hi W aawua m ge-7'7 an/19d sgaddaz 3 3 mm EEQMQ .N

Patented June 26, 1951 PRINTING TELEGRAPH RECEIVER Reginald Dennis Salmon, Croydon, England, as-

signor to Creed and Company Limited, Croydon,

England Application August 19, 1947, Serial No. 769,430 In Great Britain June 21, 1946 Section 1, Public Law 690, August 8, 1946- Patent expires June 21, 1966 7 Claims. (Cl. 178-25) This invention relates to printing telegraph receivers for page printing comprising a platen mounted in a stationary part of the machine and a carriage carrying printing means traversable parallel to the platen. The invention relates to the means for effecting line feed rotation of the platen.

One feature of the invention is a printing telegraph receiver comprising a platen mounted in a stationary part of the machine, a carriage carrying printing means traversable parallel to the platen, means for imparting line feed motion to a device separate from the platen and gearing means for rotating the said platen from said device.

By this feature, the changing of a platen becomes a comparatively easy matter, since it is unnecessary to take apart the line feed mechanism for the purpose. In this context the words line-feed mechanism include any mechanism for back-line-feed, if such be provided.

According to another feature of the invention the receiver comprises a reciprocating mechanism, means for operating said mechanism for each received signal and means operable in response to the receipt of a particular signal for causing said reciprocating mechanism to be effective to rotate the platen through a given arc.

Provision may be made for a line feed signal only, but provision may also be made for a backline feed signal to rotate the platen in the reverse direction from normal.

It may be necessary, and indeed, it is preferred, that the particular signal required to effect back line feed is a signal already allotted to some other function or to a character. In such case therefore, the receipt of an auxiliary shift signal as proposed in my copending application bearing Serial Number 761,523, filed July 17, 1947 immediately followed by the receipt of the signal in question will be necessary to effect a back-line-ieed operation. It is to be under stood, therefore, that when mention is made of a :back-line-feed signal or a signal for effecting back-linefeed such term must be taken to in clude such combination of two signals.

Mention will thereinafter be made of a formfeed signal and by this is meant a signal that is effective to cause the platen to be rotated until paper thereon comes to a predetermined position. Printin telegraph messages are often received upon printed forms and a number of these forms may be connected together in a continuous roll. It is evidently desirable that in such circumstances a received message should commence at the proper place on one of the forms. In order to achieve this, provision may be made whereby a succession of line feed operations are efiective at the receiver until the paper around the platen comes into proper position, whereupon they cease to be effective. A succession of line feed operations may result from the operator at the distant transmitter operating a key the required number of times, or preferably from the operator depressing a form-feed key. This key may cause the transmission of a succession of line-feed signals, or may cause the transmission of a formfeed signal which automatically causes the receiver mechanism to act as if it had received succession of line feed signals.

One feature of the present invention is a printing telegraph receiver comprising a platen mounted in a stationary part of the machine, a carriage carrying printing means traversable parallel to the platen, means responsive to received signals for imparting a succession of linefeed rotations to said platen, a seeker member, and means responsive to said seeker member entering a perforation in paper upon said platen for arresting the motion of said platen.

The invention will be better understood from the following description of an embodiment thereof, taken in conjunction with the accompanying drawings, in which:

' Fig. 1 is a plan view of the mechanism for effecting line-feed, back-line-feed and form-feed operations.

Fig. 2 is a view in elevation of that part of the mechanism of Fig. 1 concerned with a line-feed operation, some parts being broken awayfor a clearer view.

Fig. 3 is a View in elevation of that part of the mechanism of Fig. 1 concerned with a back linefeed operation.

Fig. 4 is a section on the line AA of Fig. 1 showing the mechanism in rest position.

Figs. 5 and 6 are similar sections showing the mechanism in different positions. (only part of the mechanism is shown in Fig. 5).

Fig. 7 is a diagram showing the instants in several cycles of operation of the mechanism at which various parts thereof are effective.

The operation of the mechanism shown in these drawings is more easily understood in the light of a general outline of the translating mechanism forming the subject matter of my said co-pending application, and is described in detail therein. r

The successively received code elements of a signal are caused to set five storage members (assuming a five unit code is used) under the joint control of the receiving magnet and a selector cam shaft released for rotation by the response of this magnet to the start element of a signal. The selector cam shaft during its rotation, releases a translator cam shaft for rotation, and a cam on this translator cam shaft moves the five storage members that have been set, as stated above, to cause them to move five vertical rods, each rod being moved in one or other direction of its length according to the character (marking or spacing) of the corresponding code element. The vertical rods are linked with corresponding code discs and with corresponding function-selector members.

The code discs serve to select a character to be printed. Their position is indicated at i in Figs. 2 and 3 in order to show the position of the mechanism of the present invention in relation to the remainder of the machine. One function-selector member 2 is shown in Figs. 2, 4, 5 and 6 and another function-selector-member 3 in Fig. 3.

When the function selector members have been set in accordance with a signal representing a function to be performed a selector bar such as 4, 5 or 6 is allowed to move under the influence of a spring 1, Figs. 2, 4, 5 and 6 or 8 Fig. 3.

Some of the selector. bars can only move into selected position if the signals representing them have been preceded by a figure shift signal. Others can only move into selected position if the signals representing them have been preceded by an auxiliary shift signal, as fully described in the above mentioned application.

Selector bar 4 is moved into selected position by spring I when a line-feed signal is received. Selector bar 5 is moved into selected position by spring 8 when an auxiliary shift signal immediately followed by a back-line-feed signal is received.

When an auxiliary shift signal is received immediately followed by a form-feed signal, the effect is that both the line-feed selector bar 4 and the form-feed-selector bar 6 move into selected position (to the right in Figs. 4, 5 and 6) the latter being moved by a spring (not shown) similar to springs 1 and 8. The arrangements for causing these movements of the selector bars will be clear from the description of the translating mechanism in the application above referred to. The actual mechanism for moving a function selecting member into selected position forms no part of the present invention; for the particular embodiment described it is only necessary that some mechanism be provided for causing the movement of the appropriate selector bars in response to the receipt of the appropriate signals.

The invention relates to a page printing telegraph receiver in which the platen 9 (Figs. 4, 5 and 6), around which is wound the paper H] upon which printing is to take place is mounted for rotation in a stationary part of the framework of the machine. The printing carriage, upon which is mounted the typing means, is traversed parallel to the platen for the printing of successive characters in a line of printing. For each line-feed operation, whether forward line-feed or back-line-feed, the platen must be rotated through a given are.

In the embodiment shown the line feed mechanism, instead of acting directly upon the platen 9, operates to rotate a gear wheel l I, Figs. 1, 5

and 6 which meshes with an idler gear wheel (not shown) which in turn meshes with a gear wheel (not shown) fixed to the platen 9. The gear wheel ll is fixed to a shaft I2 to which are also fixed ratchet wheels l3 and I4. Mounted to be freely rotatable about shaft 12 are two plates [5 and 15. Fig. 2 shows the plate 16 and the ratchet l4 partly broken away. A pawl H is pivoted on a pin i8 fixed to plate 15 and is urged by a spring 19 for rotation into engagement with ratchet wheel 13. Another pawl 20 Fig. 3 is pivoted on a pin 2| fixed to plate 45 and is urged by a spring 22 for rotation into engagement with ratchet wheel M.

The pawl H is held out of engagement with the ratchet wheel 13 by a line-feed-suppressorlever 23 pivoted on a stub-shaft 24 and engaging a pin 25 fixed to pawl ii. The pawl 20 is held out of engagement with the ratchet wheel M by a backeline-feed-suppressor lever 26 also pivoted on the stub-shaft 24 and engaging a pin 21 fixed to pawl 20. A frame 28 is also pivoted on the stub-shaft 2d and carries tappets 29 and 30 (as well as a third tappet 3i referred to hereinafter) which engage line-feed-suppressor lever 23 and back-line-feed-suppressor lever 25 respectively and hold these levers in the positions shown in Figs. 2, 3 and 4 against the pull of springs 32 and 33 respectively. Tappet 29 is however, not shown in Figs. 4 and 5 since it would obscure the view of tappet 3|.

One arm 34 of the frame 28 is bent as shown in Figs. 1, 2 and 3 and one end of a link 35 fits on a pin 35 on the bent portion 31. The other end of link 35 fits on a pin 38 on plate l6. Plate [6 is connected by a link 39 to a lever 46 fixed on a stub shaft 4i journalled in bearings (not shown) in the framework of the machine. Fixed to stub shaft 4! is a lever 52' connected by a link 43 to a lever 44 fixed to a sleeve 55 (Fig. l) journalled on a pin 46 mounted on the fixed part of the framework. Fixed to sleeve 45 is a lever 41 carrying a cam-follower 58 and urged by a spring 49, Fig. 2 to hold the cam-follower 48 in engagement with a cam 50.

Also fixed to stub-shaft M is a plate 5! on which is pivoted at 52 a member 53. Member 53 carries an adjusting screw 54 working in a slot 55 in plate 5|. Member 53 is connected by a link 55 to plate 15. Member 53 is shown in one position in Fig. 2 and in another position in Figs. 4 and 6 and it will be noted that a given movement of plate 5! will result in twice the movement of plate l5 for the position of member 53 in Fig. 2 from that which will result for the position of member 53 in Figs. 4 and 6. By clamping the screw 54 in either of its extreme positions, therefore, the mechanism may be set to feed at each operation either the space of a single line or of two lines.

The operation of the mechanism above described will now be described, first for the case in which no line feed operation takes place, secondly for the case of a forward line-feed operation and thirdly for a back-line feed operation.

During the rotation of the translator cam-shaft above referred to, a function cam shaft is released for rotation for one revolution, as described in the above mentioned prior application. Cam 5!] is one of the cams on the function cam shaft and thus is rotated each time a signal is received. Cam 58 through the linkagesabove described rotates plate i5 in an anti-clockwise direction about shaft l2 and plate I6 in a clockwise direction about this shaft. 'Plate it rotates, through link 35, frame 28 about shaft 24 and thus tappets 29 and 30 are removed from engagement with line-feed suppressor lever 23 and back-line-feed-suppressorlever 26 respectively. These levers are however drawn by springs 32 and 33 to follow the tappets 29 and 30. If, however, the received signal has levers 23 and 2B and thus prevent these levers Y from moving more than a very small distance.

These levers therefore prevent the respective pawls ll and 2i from engaging with their corresponding ratchet wheels l3 and I l. The plates [5 and i6 and thus the pawls ll and 2| are reciprocated without any effect on the line feed mechanisms.

The effect of the receipt of a line-feed signal will now be described. Fig. 7 will be of assistance in following the sequence of operations. Following the receipt of such signal the line-feed selector bar 4 is moved to the right in Fig. 2. The projection 5? is therefore out of the path of movement of the line-feed-suppressor-lever 23, as shown in Fig. 2. The projection 58 Fig. 3 on the back-line-feed selector bar 5 is, however, still 1n the path of movement of the back-line-feed-suppressor lever 26. When plates l5 and it have been rotated through a very small arc and frame 28 has been lifted, line feed suppressor lever 23 Fig.

- 2 moves beyond its suppressing position under the pull of spring 32 and pawl ll is rotated by its spring I9 into engagement with ratchet wheel I3. Further rotation of plate l5 carrying pawl H with it causes rotation of ratchet wheel l3 and with it gear wheel ll. Just before the highest part of cam 50 comes into engagement with cam-follower 48, an arm 59 Figs. 4 and 6 fixed to hub 4|, engages a pin fill on the end of a lever 6!, pivoted at 62 and rotates it against a spring 63 to bring an overshoot stop 64 on lever 6! between the teeth of gear wheel ll so that it is held against overshooting the required degree of rotation.

As the cam 50 continues its rotation after having passed the highest point, the plates I5 and is are rotated in the opposite directions and the overshoot stop 64 is Withdrawn from engagement with the gear wheel II. This wheel is held in position by a jockey roller 65 held against the wheel by a spring 66. During the return movement of frame 28 the tappet 29 Fig. 2 presses on the line-feed suppressor lever 23 to move it with the frame 28 back to initial position and shortly before the end of the return movement of the frame tappet 3i) re-engages back-line-feed-suppressor lever 26 Fig. 3 and restores it to initial position.

If a back-line-feed-signal be received, the line feed selector bar 4 will be in unselected position and the back-line-feed selector bar 5, Fig. 3, will move into selected position, in which position the projection 58 will be removed from the path of movement of the back-1ine-feed-suppressor-lever 28. A cycle of movement of the mechanism will take place in a manner similar to that described above save that the line feed suppressor lever 23 will be prevented from following the frame 28 whereas the back-line-feed-suppressor lever 26 will be drawn by its spring 33 to follow the frame 28 in its upward movement and the pawl will thus be allowed to be pulled into engagement with ratchet wheel I4. During the rotation of plate It, therefore, the ratchet wheel M will be rotated in a clock-wise direction as seen in Fig. 3 and the gear wheel H and consequently the platen 9 will be rotated to bring a line on the paper that was selectable to be now selectable.

. 6 previously above the line of printing into of printing.

It is to be noted that a jockey roller similar to the jockey roller 65 is provided for holding the gear wheel fixed to the platen 9.

The arrangements for form-feed will now be described. If the operator at a transmitter station connected to the receiver having the mechanism shown in the drawings wishes to synchronise the position of the paper at the receiver with that in his home receiver to ensure that a message to follow will commence to be printed on the first line of one of the forms into which the paper is divided, he first positions the paper in his home receiver to the correct position and actuates the auxiliary shift key and then the form feed key. As explained in my said prior application above mentioned the auxiliary shift signal positions the code-function-selector members so that an auxiliary shift selector bar is moved into selected position and a vane similar to other codefuncton-selector members, is set in such position as to cause certain selector bars, not previously One ofthese bars is the form-feed selector bar 6, Figs. 4, 5 and 6. Thus when the form-feed signal follows the auxiliary shift signal the form feed selector bar 6 is moved to the right in Fig. 4, It should here be noted that the selector bar 6 is shown in Figs. 4, 5 and 6 a little to the left of the respective correct positions, in order that it may be clearly distinguished from the line-feed selector bar 4.

In the prior application above referred to inthe line stances are given of selector bars that are selectable when the above mentioned vane, there called a secondary shift vane, is in either the set or the unset position. In carrying out the present invention it is arranged that the line-feed selector bar 4 is selected on receipt of the appropriate signal as above described when the secondary shift vane is in the unset position and also is selected upon receipt of the form-feed signal when the secondary shift vane is in the set position. In fact the form feed signal is identical with the line feed signal but operates as a form feed signal when it follows the auxiliary shift. The consequence is that when the auxiliary or secondary shift signal, immediately followed by the form feed signal is received both selector bars 4 and 6 move to the right in Fig. 4.

A projection 6'! on the selector bar 6 rests against a projection on an interposing member 68 pivoted at 69 and tending to be drawn to the right in Figs. 4, 5 and 6 by a spring it. When the selector bar 5 moves to the right in these figures the interposing member 68 is drawn by spring Ill to follow it but is arrested after a very small movement by a tooth ll on a latch 72. The latch 12 is pivoted on the shaft 2:3 and is drawn upwards by a spring 13 so that its end rests against a turned-over portion l l on the end of formfeed-lever i5. This form-feed-lever i5 is also pivoted on shaft 24 and urged clockwise by a spring 18. It is held inthe position showninFig/l against the pull of spring l6 by tappet 3E on frame 28 which engages a flat on the upper side thereof. When frame 28 starts to be moved by cam 56, the form-feed-lever 15 moves a short distance only being arrested by two different means. If the form-feed-selector bar 6 is in unselected position, the form-feed-lever 15 is arrested by the turned over portion 14 coming in contact with a projection H on bar it so that, in such case the form-feed-lever 15 cannot follow the movement of frame 28.

. arm l8 of the bifurcation is engaged by a latch lever is pivoted at 8% and drawn by a sprin 8! into position to arrest the form-feed-lever 15. Since the line-feed-selector bar 4 is in selected position the projection 5i thereon is out of the path of movement of line-feed-suppressor lever 23 which accordingly follows the frame 28 in its clockwise movement. Pawl I? therefore engages ratchet wheel l3 and imparts a line-feed rotation to the platen 9. Just before plate l5 completes the full extent of its anti-clockwise rotation a pin 82 thereon engages latch lever 79 and rotates it against the pull of spring Bi out of engagement with arm 18 of form-feed-lever 15. The form-feed-lever '15 now rotates clockwise. A second arm 83 of the bifurcation of this lever is in engagement with a pin 84 on a seeker member 85 and rotates this seeker member to bring the end thereof into contact with the paper ill on the platen 9.

The paper It is provided with perforations at intervals and a groove is formed in the platen 9 so that if the seeker 85 enters a perforation it move into the groove. The perforations are so located that if a perforation is opposite the seeker 85 the first line of a form is in position for printing to take place thereon. These perforations may, in the case of sprocket fed paper, be formed as elongations parallel to the axis of the platen of the perforations normally provided for engagement by the teeth of the sprocket wheel.

If there is no perforation in the path of the seeker 85, the seeker comes into contact with the paper iii which arrest it and, prevents the forfeed-lever '55 from moving to the full extent permitted by the tappet 34 on the frame 28.

Reference to Fig. '7 will show the relative timing of the various actions that take place. This figure shows the operations during several succession rotations of the cam 50. At the commencement of the first rotation it is assumed that the line-feed-selector bar has been selected as above described. It is then assumed that the form-feed signal is received. The second rotation of the cam 58 shown is that immediately following the receipt of this signal, the intermediate rotation following the receipt of the auxiliary shift signal being omitted. It is also assumed that during the second rotation shown the seeker 85 does not enter a perforation in the paper.

Since, as stated above, the lever 75 does not move to the full extent possible, the frame 28 in its return movement moves the lever 15 with it and latch 12 remains in the path of interposing member 63.

It is assumed that cam 58 continues to rotate. This may be accomplished in several different ways. I

(a) the actuation of the form-feed key by the distant operator a plurality of times so that the form-feed signal is received a plurality of times. As the position of the code-function-selector members does not change upon the repetition of the same signal, the selector bars 4 and 6 remain in selected position and cam 50 completes one rotation in respect of each received signal.

(2)) the operation of the form-feed key by the distant operator causes the form-feed signal to be sent automatically a plurality of times.

The same consequences at the receiver follow.

(c) the operation of the form-feed key by the distant operator causes the form-feed signal to be sent once only but the receipt of this signal causes continued rotation of the cam 50 until automatically arrested at the receiver.

On any of these assumptions, however, during each rotation of cam 50 a line feed operation will take place and seeker will immediately thereafter be moved into contact with the paper ID on the platen 9. If now this seeker 85 finds a perforation in the paper, form-feed lever 15 will move the full extent permitted by tappet 3| on frame 28 and will carry latch 72 with it. Latch 12 is now moved to a suflicient extent to be clear of interposing member 68 which will move to the right a slight extent until a projection 86 thereon comes against a projection 8'! on the underside of the lever 23. Fig. 5 shows the position of the mechanism at this point in its operation.

The frame 28 in its return movement moves the form-feed lever 15 and the line-feecl-suppressor lever 23 counter-clockwise. The seeker 85 is withdrawn from the perforation in the paper 10 and the lever 23 moves the pawl H from engagement with the ratchet wheel 13. The right hand end of lever 23 rises and allows the projection Bl thereon to move clear of projection 85 on interposing member 53 whereupon the interposing member 68 moves further to the right to bring projection 86 thereon under projection 81 on lever 23. The timing of the operations just described is shown in Fig. 7 in connection with the penultimate rotation of cam 56 shown there- Cam 50 may now rotate one or more times but no line-feed operations will take place corresponding to such rotations despite the fact that the form-feed selector bar 6 and line-feed selector bar 4 remain in selected position, because projection 88 on interposing member 68 remains in engagement with the underside of projection 81 on lever 23 and prevents that lever from following the movement of frame 28. Consequently pawl IT is held out of engagement with ratchet l3 and no feeding motion of the paper takes place.

Fig. 6 shows the position of the mechanism during one of these subsequent rotations of cam .58 at the moment when the seeker 85 has entered the perforation in the paper (which it will do at each such revolution since the paper will remain in the same position). The tooth H on latch 22 is behind interposing member 68 and thus latch 12 can follow form-feed lever M during each reciprocation.

When a new signal isrreceived and form-feed selector bar 5 is restored to unselected position, projection 67 pushes interposing member 68 to the left in Fig. 6 and the tooth H on latch 12 snaps back into the position shown in Fig. 4.

It has been described in my said copending application above referred to how the mechanism of a printing telegraph receiver may be arranged so that the movement of a particular selector bar into selected position causes the rotation of the function selector cam sleeve for a plurality of revolutions. In such case a detent, normally holding the function cam sleeve against rotation, is held out of operation whilst the selector bar is in selected position. If it be desired that the formfeed key at the distant transmitter should cause the form-feed signal to be sent once only, similar arrangement could be used in the practice of the present invention, the form-feed selector bar 6 being used to hold the said detent out of operation. Such detent could then be tripped (to arrest cam 50 at the end of a revolution) by movement of the interposing member 68 into the position in which it holds line feed suppressor lever out of action.

What is claimed is:

1. A page printing telegraph receiver comprising a platen mounted in a stationary part of said receiver, a movable carriage traversable in a plane parallel to the axis of said platen, printing means mounted upon said carriage, a reciprocating mechanism, two oppositely directed ratchet wheels rotatably mounted on said mechanism, a gear wheel fixed to both of said ratchet wheels, a pair of pawls, each of said pawls cooperating with a different one of said ratchet wheels, means for selectively operating said mechanism thereby to cause one of said pawls to operate on its corresponding ratchet wheel, gearing means disposed between said platen and said gear wheel, whereby said platen is caused to rotate through a given are and in a given direction so as to effect a line feed or a back line feed.

2. A page printing telegraph receiver comprising a platen mounted in a stationary part of said receiver, a movable carriage traversable in a plane parallel to the axis of said platen, printing means mounted upon said carriage, two oppositely directed ratchet wheels, a gear fixed to both of said wheels, gear means disposed between said platen and said first named gear, a pair of pawls, each of said pawls cooperating with a difierent one of said wheels, a reciprocating mechanism, said pawls mounted on said mechanism, rotating cam means, said cam means coupled to said mechanism, signal responsive means, means controlled by said signal responsive means for permitting one of said pawls to operate on its corresponding wheel whereby said platen is caused to rotate through a given are and in a given direction so as to efiect a line feed or a back line feed.

3. A page printing telegraph receiver as claimed in claim 2 wherein said pawls further comprise spring means for rotating each of said pawls into engagement with its corresponding wheel, and said means controlled by said signal responsive means for permitting one of said pawls to operate on its corresponding wheel comprises a pair of pivotally mounted members, said members in contact with said pawls for normally holding same is disengagement with said wheels, and selector means coupled to said members, said selector means operable in response to line feed signals and back line feed signals respectively.

4. A page printing telegraph receiver as claimed in claim 3 wherein said selector means comprise a pair of selector bars, each having an abutment thereon, each of said bars cooperating with a. different one of said members each of said members normally restrained from movement by the abutment on its corresponding bar, means for selectively moving said bars out of the 10 path of said members in response to received line signals whereby the pawl associated with the unrestrained member engages its correspon in wheel for that part of the cycle of said reciprocating mechanism during which a rotation of said platen is to be efiected.

5. A page printing telegraph receiver compris ing a platen mounted in a stationary part of said receiver, said platen having an annular groove formed around the circumference thereof near one of the extremities of said platen, said platen adapted to carry message paper therearound, such paper to be provided with perforations at predetermined positions thereon in register with the groove'in said platen, a movable carriage traversable in a plane parallel to the axis of said platen, printing means mounted upon said carriage, two oppositely directed ratchet wheels, and a gear fixed to both of said wheels, gear means disposed between sad platen and said first-named gear, a pair of pawls, each of said pawls cooperating with a different one of said wheels, a reciprocating mechanism, said pawls mounted on said mechanism, rotating cam means, said cam means coupled to said mechanism, a seeker member pivotally mounted in a stationary part of said receiver, said member in register with the groove in said platen and adapted to be urged against the perforations in the message paper therearound and adapted to enter said perforations, signal responsive means, means controlled by said signal responsive means for permitting one of said pawls to operate on its corresponding wheel, said last-mentioned means under control of said seeker member, whereby said platen is caused to rotate through a given are and in a given direction so as to effect a line feed or a back line feed.

6. A page printing telegraph receiver as claimed in claim 5 wherein said means controlled by said signal responsive means for permitting one of said pawls to engage its corresponding wheel further comprises threadedly adjustable means.

7. A page printing telegraph receiver as claimed in claim 5 further comprising a rotatable cam for operating said reciprocating mechanism, means for releasing said cam for rotation for each received signal and means operative when said seeker member enters the groove in said platen to arrest said cam upon the completion of a rotation thereof.

REGINALD DENNIS SALMON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

